A Guideline For The Use, Inspection And Maintenance Of .
Deck, balcony and window safetyA guideline for the use, inspection and maintenanceof decks, balconies and windowsMarch 2017
Deck, balcony and window safety: Guideline – Building Industry and PolicyTable of ContentsTable of Contents . 2Why this guideline?. 3What standards apply? . 3Coroner Reports42010 Coroner’s report into deck collapse42012 Coroner’s report into accident on a damaged deck41. Decks and balconies . 6Balustrade requirements6Stairs7Windows72. Safety . 8ChildrenAdults8103. Maintenance issues to consider . 11Termite attack11Decay and moisture1112Coastal effects13Loads134. Inspecting decks and balconies . 14Components of decks and balustrades to regularly inspect141415Check bearers and joists for warping or cracking1616Planning on extending, renovating or repairing. 18Contacts for advice and/or inspection services . 18Acknowledgements . 19Glossary . 19March 2017Page 2 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyWhy this guideline?This guideline has been developed to helpbuilding owners and occupiers, builders andinspectors carry out inspections onbalustrades, decks and balconies in orderto check the safety of these structures.The guideline may be useful for industryprofessionals. However, the information isnot a replacement for technical standardsused by industry.Owners and managers of non-residentialbuildings with a deck or balcony, such asrestaurants, hotels and clubs, may also findthis guideline relevant.Adequate maintenance of decks and balconies can savelivesThe guideline also provides useful adviceabout safety issues associated with elevated floors and openable windows.In recent years a number of deaths and serious injuries have occurred as a result of falls from decks,balconies and windows, or from the collapse of decks and balconies.Statistics from pre-purchase inspection agencies suggest that approximately six per cent of Australianhouses have a timber deck or balcony and about two per cent of these may cause potentially fatal injuriesif they collapsed or if the balustrade or railing failed. These numbers are estimated to be even higher inQueensland where, due to our unique climate, timber decks are a major feature of many homes. Some ofthese decks may have been constructed inadequately or illegally and could now be in danger of collapse.Building owners especially need to consider risks and consequences arising from an injury or deathassociated with a failing balustrade or deck, which is shown to be in poor condition or illegally built.If you own a building with a balcony or deck—whether it is made from timber, metal, concrete or anothermaterial—you should ensure it is inspected carefully for decaying timbers, unstable balustrades,corrosion and cracking of concrete.RememberIn Queensland between 2002 and 2012 more than 20 people have died and hundreds have been injuredafter falling from decks or balconies. A small but significant proportion of cases have been associated withstructural failure of the deck or balcony.Had people been more aware of the dangers associated with elevated areas and the importance ofadequate maintenance of decks and balconies, some of these deaths and injuries may have beenprevented.What standards apply?The National Construction Code (NCC) provides the requirements for new building work throughoutAustralia. Unless new building work is occurring, a building is only required to meet the standards in forceat the time of the most recent building approval. The building standards mentioned in this guideline arefrom the current NCC and apply to new building work. Existing buildings that are the subject of additions,alterations or renovations may also be required to meet the NCC provisions.March 2017Page 3 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyCoroner Reports2010 Coroner’s report into deck collapseIn June 2010, the Brisbane Coroner released findings from an investigation into a death caused by adeck collapse. The deck was constructed prior to the 1940s using methods that are not common bytoday’s standards.The Coroner recommended occupiers of all residential dwellings that include a timber deck orbalcony (particularly those built before the 1940s) have them checked for structural integrity.Figure 1 shows a typical construction method for pre-1940s decks. The beam (or bearer) is cogged outto hold the joist. The joist is held in place with nails. This was the joining method used on the collapseddeck.In this type of construction method, the ends of the joists are concealed by the bearer in the area wherethe joist rests. Over time, the nails can rust out, the beam can bow outwards and the joist can separate,potentially resulting in structure failure or collapse as shown in Figure 2.It is important to note that this is just one way in which a deck may fail. Other areas should be inspectedon a regular basis to check the structure’s reliability and integrity.Figure 1: Pre-1940s deck constructionwith a cogged out beam holding thejoist with nails.March 2017Figure 2: Old nails can rust outcausing structure to collapsePage 4 of 21
Deck, balcony and window safety: Guideline – Building Industry and Policy2012 Coroner’s report into accident on a damaged deckIn September 2012, the Rockhampton Coroner released findings from an investigation into a deathcaused by a decayed decking board.The Coroner recommended that State agencies provide guidance about the inspection of deckingboards for signs of deterioration that may compromise their structural integrity.The coroner further recommended that Standards Australia design an Australian Standard toestablish how deck inspections should be conducted.One of the decayed decking boards from the accident.March 2017Page 5 of 21
Deck, balcony and window safety: Guideline – Building Industry and Policy1. Decks and balconiesBalustrade requirementsIn Queensland there are strict requirements for the design and construction of balustrades and railings.Under the NCC, a balustrade or barrier is required whereRememberpeople could fall one metre or more from a floor oraccessible roof of a building. Put simply, where a differenceWhere a deck or balcony is one metre orin height from the deck or balcony to the ground or anotherhigher above the ground, balustradeslower level is one metre or more, a balustrade of at leastneed to be at least one metre high.one metre in height is required.Retaining walls do not require a balustrade unless they areassociated with a path of travel to, from or betweenbuildings. However, for other retaining walls, it is a goodidea to provide a balustrade or other barrier in situationswhere there is a risk of a person falling from the retainingwall.For decks more than one metre abovethe ground, openings in balustrades,including decorative balustrades, cannotbe greater than 125 millimetres.For decks more than four metres abovethe ground, balustrades cannot have anyclimbable elements located between 150millimetres and 760 millimetres from thefloor.Requirements for balustrades differ depending on the heightof the deck or balcony above the ground. For decks orbalconies more than one metre above the ground, abalustrade cannot have any openings greater than 125 millimetres, to help prevent people from fallingthrough them. This is also a requirement for decorative balustrades. For decks or balconies more thanfour metres above the ground, a balustrade must also not have any climbable elements, such ashorizontal rails, located between 150 millimetres and 760 millimetres from the floor.Balustrades must be constructed so that they can resist the forces reasonably expected to be placedupon them. These forces include people leaning against them and strong winds.Figure 3: Balustrade or other barrier construction (Courtesy: Australian Building Codes Board).March 2017Page 6 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyStairsBalustrades or railings on stairs are equally as important as those for decks and balconies. When peopleascend or descend stairs, they generally gain support using the railing, which can also act as a barrier.Therefore, stairs require a similar barrier to decks and balconies, and it is important that thesebalustrades are sturdy and can withstand appropriate pressures, such as the force of a person.For stairs, a barrier of at least 865 millimetres high above the ‘nosing’ of the stair treads is required. The‘nosing’ of the stair treads can be measured by placing a string line, or straight object, where each stairtread begins, forming a slope. The measurement of 865 millimetres can be taken vertically anywherealong this line to the bottom of the balustrade. As with balustrades for decks and balconies, gaps inbalustrades on stairs cannot have openings greater than 125 millimetres. For stairs more than fourmetres in height, a balustrade must also not have any climbable elements, such as horizontal rails,located between 150 millimetres and 760 millimetres from the floor.Stairs require a similar barrier to decks and balconies.WindowsElevated openable windows, which are common in older Queenslander style houses and units, should beprotected to prevent falls. Generally, for bedroom windows with a 2 metre or more drop to the surfacebeneath and where the window opening is less than 1.7 metres above the floor, window protection isrequired. This may be in the form of a device to restrict the window opening or a screen with securefittings. The device or screen must: not permit a 125 millimetre sphere to pass through the opening; resista 250 Newton outward horizontal action (approximately 25.5 kg force); and have a child resistant releasemechanism if the screen or device can be unlocked or removed.Where a child resistant release mechanism is used, or there is a 4 metre or more drop to the surfacebelow, a barrier is required. Similarly to the balustrade requirements, a 125 millimetre sphere cannot passthrough the barrier and no horizontal climbable elements are permitted between 150 and 760 millimetresfrom the floor.March 2017Page 7 of 21
Deck, balcony and window safety: Guideline – Building Industry and Policy2. SafetyChildrenIn the 11 years from 2002 to 2012, data collected by the Queensland Injury Surveillance Unit (QISU) hasrecorded 936 presentations to participating emergency departments resulting from falls from a balcony.Note: It has been estimated that the QISU data represents less than a quarter of all paediatricpresentations in Queensland resulting from a fall1. QISU data is not collected in the Gold Coast andSunshine Coast areas where high rise developments predominate.Of the QISU data, the peak age for balcony falls was 0-4 years, with presentations in this age groupaccounting for 41% of cases.Severe injuries requiring immediate resuscitation were recorded in 3% of cases, however 70% of of thosesevere injuries were in children aged 0-4 years.Nearly one third of patients required admission or transfer to another facility after falling from a balcony.Helping prevent falls from decks and balconiesThe most common reasons children fall froma deck or balcony are: climbing horizontal parts of balustrades passing through the horizontal parts of abalustrade climbing on furniture on a deck or balcony lack of supervision of children on a deckor balcony.Children represent a large proportion of hospitalisations fromfalls from high levelsKidsafe Queensland and QISU advise that parents can take a number of precautions to help ensure thesafety of children around decks and balconies and recommend that buildings occupied by children shouldbe adapted to make them safe.Where a deck or balcony is more than one metre above the ground, there should be absolutely noclimbable objects placed near to the balustrade. Any furniture placed on the deck should be: positioned well away from the balustrade1It is estimated that data is captured in approximately 80% of injury cases presenting to QISU participating hospitals, and thatpresentations to participating hospitals represent approximately 25% of all paediatric presentations in the state and 20% of alladult presentations. Therefore, numbers presented above should be adjusted accordingly in order to estimate the total number ofpresentations state-wide.March 2017Page 8 of 21
Deck, balcony and window safety: Guideline – Building Industry and Policy heavy enough to discourage children from moving it close to the balustrade.One of the best ways to help prevent a child from falling from a deck or balcony is by constantlysupervising them. Also, if a deck or balcony is inaccessible to an unsupervised child, the likelihood of afall is dramatically decreased. Child access to decks and balconies can be restricted by installing highlocks and latches and self-closing devices on the access points.Helping prevent falls from windowsThe most common reasons children fall from windows are: furniture placed below openable windows failure of flyscreens to protect openings non-safety grade glass (often in older buildings where this requirement did not apply at the time ofconstruction)Building design can play an important part in helping prevent injuries from falls from windows. QISUrecommends that where rooms may be used by children, larger openable windows should be avoidedand higher positioned louvre-type windows should be used instead.Despite the technical provisions of the NCC, QISU suggests it would be good practice that where it islikely a child can gain access to a window, the opening should be limited to a maximum of 100millimetres.2 To do this, windows can be fitted with devices (to allow a window to only open 100millimetres for example) or barriers (metal mesh or bars with no opening greater than 100 millimetres).Natural ventilation of rooms will also need to be considered where windows are fitted with these devicesor barriers.RememberPositioning air-conditioners or other climbable objects on a balcony or deck close to a balustrade should beavoided or made non-climbable as these can be used as a foothold for children to climb on.Similar to the pool safety requirements, it is recommended that a non-climbable arc of 900mm be maintainedoutwards from the top of a balustrade.Also, do not place beds, furniture or other climbable objects beneath or near openable windows.While these measures are not a requirement of the NCC, they are best practice and strongly encouraged topromote the safety of children.Fly screens may be effective barriers for insects, but they do not prevent childrenfrom falling out of windows. A metal mesh or grill is a suitable alternative that willallow a breeze through the building.Avoid placing climbable objects close to balustrades or openable windows asshown in the picture to the right.2Note - The NCC specifies a 125mm maximum opening. Home owners can choose to apply the more stringent QISUrecommendation however.March 2017Page 9 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyAdultsThe most common reasons for adults falling from balconies or decks are: the effects of alcohol or drugs sitting on top of the balustrade balustrade failure.Numerous deaths associated with falls from decks and balconies have been due to alcohol or drugconsumption. Most of these falls occur in high-rise buildings. Other known cases of falls have involved aperson climbing from one balcony to another, or over a balustrade.RememberWhen using a deck or balcony, you need to be aware of the dangers and effects that alcohol or drugscan have on your judgement and balance.Never climb from one balcony to another, or over a balustrade, especially in multistorey or high-risebuildings.Numerous deaths have been associated with falls from high-rise balconies.March 2017Page 10 of 21
Deck, balcony and window safety: Guideline – Building Industry and Policy3. Maintenance issues to considerOver time decks and balconies will deteriorate. It is important to undertake routine maintenance to ensuretheir ongoing safety. This chapter addresses key maintenance considerations such as termite attack,decay and moisture, coastal effects and loads on the structure.Termite attackTermites can be a major problem in timber structures. Timber in the ground should be termite resistant ortreated in accordance with the relevant standards in the NCC.All timber construction should have a termite management system, either physical or chemical, to helpprotect it and to help ensure termites cannot bypass protection systems to adjacent structures. Termitemanagement systems must be designed so they can be readily and regularly (6 to 12 months) inspectedand maintained.To reduce termite attacks it is also important to ensure all timber is removed from around buildings,including timber stacks, old tree stumps, sleepers and logs.Termites also prefer humid conditions so keep air under the building or structure dry by improving subfloor ventilation, drainage and access.Decay and moistureWhat to look for: any decaying timber that forms part of the deck or balcony discoloured or blistered paint depression of timber termite mud nests any build-up of soil around the base of the timber—if timber is untreated it should not be in contactwith soil fine ‘sawdust’-type material around or below timber—this can signal that termites are active.Decay occurs when timber decomposes due to high levels of moisture. It often occurs when two pieces oftimber are in contact, trapping water and moisture. Timbers exposed to the elements need to beadequately painted to help protect the timber from contact with water and moisture.To reduce the likelihood of decay, any areasof the deck or balcony that are frequentlydamp should be addressed immediately.Dampness can occur when pot plants withoutbottom plates or feet are placed on the deckor balcony. Soil and other debris should alsobe cleared away from the deck or balcony,bearers or joists (if it is a low deck or balcony),and posts or supports.Keep trays or feet under pot plants to reduce moisture onIf decay occurs in structural timbers (suchdeckingas posts, bearers or joists), seek expertadvice to establish the implications for the structural integrity of the deck or balcony.March 2017Page 11 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyAny structural problems need to be addressed immediately as well as the causes of the decay andmoisture. There is little or no benefit in repairing the damage if it is only going to reappear soon.If decay is found in deck or balcony posts, joists, bearers or handrails or balusters, these members willrequire replacement with new durable timber as it may not be economically feasible or practical to repairthem to a structural standard.For a temporary repair in small non-structural areas, decayed timber can sometimes be cut away and anew piece of timber adequately joined to the remaining timber. If the damage is confined to a very smallarea, an epoxy-based repair kit can sometimes be used to fill the damaged area once it has been cutback to sound timber and the new surface of the timber can be treated with a suitable coating. Suchmeasures are only temporary solutions and will only delay the failure of the structure.Water damage to your deck or balcony may also occur at the junction of the floor material and toelements such as timber posts or handrails.In these areas there is the potential for water to lie on horizontal surfaces such as bearers or joists,particularly where such structures are enclosed.Care should be taken to inspect these sections for decay and to do this adequately may requiretemporarily removing decking boards.Water left on timber can cause fixings to deteriorate and rustRemoving this decking board has revealed a decayed joistMarch 2017Page 12 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyCoastal effectsDecks and balconies on properties near the coast can have a higher risk of potential failure. This is dueto the harsh environment and corrosive effects of salt, sand and wind, which can affect unprotectedtimber and steel structures, reinforcing steel and fixings such as bolts and fixing plates. Such corrosioncan lead to mechanical or abrasive wear. It can also cause timber to break down adjacent to rusted metalconnections and for steel to corrode.One of the best ways to help protect timber in this type of coastal environment is to apply and maintain anoil-based paint on exposed timber surfaces such as bearers, joists, posts and balustrade systems.Steel used in coastal areas should, as a minimum, be hot dipped galvanised and additionally, mayrequire specialized paint coatings. This protection should be carried out at the time of construction to helpprevent initial deterioration. Steel that is left unprotected and starts to rust or corrode should be dealt withpromptly to prevent further deterioration. In severe coastal conditions such as proximity to breaking surf,all connections and fasteners should be stainless steel.LoadsBuilding elements need to be designed and engineered to withstand certain loads.Loads are an important aspect to consider when you are establishing the stability and integrity of a deckor balcony. It is often easy to overlook the load that the combined weight of a number of people exerts onthe structure. Every time 13 people gather on a deck or balcony, they exert the same force as a smallcar. This force is greatly increased when the people jump, dance or move about. Large pots, waterfeatures and furniture can also contribute to the loads applied to your deck or balcony.What to look for: avoid installing heavy objects such as spas on a deck or balcony, unless the deck or balcony hasbeen specifically designed to withstand this extra load avoid excessive jumping, dancing or other movement on a deck or balcony, unless the deck orbalcony has been specifically designed to withstand this extra load remember that as a deck or balcony ages, elements generally deteriorate, reducing its ability towithstand the loads for which it was originally designed avoid having large numbers of people gather on a deck or balcony at once, unless the deck orbalcony has been specifically designed to withstand this load.March 2017Page 13 of 21
Deck, balcony and window safety: Guideline – Building Industry and Policy4. Inspecting decks and balconiesDecks and balconies require regular and effective maintenance to help ensure their long-term safety. Thefrequency of this maintenance depends on the materials, type of finish, climate and the degree ofexposure to the weather.It is important to allow access for visual inspections of a deck or balcony. Of particular interest are theareas where timbers join, where metals are in contact and areas providing ground support. Enclosing theunderside of a deck or balcony by cladding between the posts or installing a ceiling, is not recommendedbecause it can prevent the ability to visually inspect these areas.Helpful hintTake photos of your deck or balcony after completing building work. The section below outlines the keycomponents that should be photographed to assist with future inspections. Use these photos asreference points when carrying out inspections to identify any changes or movement of components.Components of decks and balustrades to regularly inspectFixingsFixings, including post brackets, should be free from rust, bending or fractures. Although rust can occurmore rapidly in coastal regions, products can be applied to metal fixings or components to slow orprevent this process.For a weather-exposed deck or balcony, all fixings such as nuts, bolts, screws and nails should be metalwith non-corroding properties. In most cases, hot dipped galvanised fasteners should be used. However,in some highly corrosive coastal atmospheres, stainless steel fixings will be needed.What to look for Bending or stress of post brackets—in most cases these brackets will be above ground level, whichwill make visual inspection easier. Deterioration of nuts, bolts, screws or nails—these fasteners can be integral to the deck or balconyand need to be free from deterioration. Rusting metal may be easier to find as it may leave a markon the connecting timber or paint. Identify, repair and replace these areas as soon as possible.Inspect post brackets for bending or stressingMarch 2017Page 14 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyWhat to look for: rusting of steel posts warped, cracked or damaged posts signs of decay in timber.During inspections it is good practice to remove bolts to see their internal conditionPostsWhere the deck or balcony is raised and relies on posts for support, adequate engineering is required toensure the strength and stability of these components.Deterioration and subsequent failure of posts can result in death or serious injury to people and damageto property. Timber should be treated appropriately if in the ground or be of a species that will notdegrade in soil.Check timber posts for decay where bearers and other timbers are in contact with posts. Signs of decayinclude a fungus type growth on the timber, timber becoming spongy and fibrous and failure of the timber.Steel posts in the ground should be checked for signs of rust and deterioration as water can pool aroundthese areas.BracingBracing is often used to support a deck or balcony, helping prevent it from moving under load. Decks andbalconies can come under considerable stress from swaying or twisting. If bracing fails, there is asignificant risk of harm being caused to people and property. It is therefore important to inspect anybracing of a deck or balcony to ensure there has not been any excessive structural movement.What to look for: warped, cracked or damaged bracing elements fixings that are coming loose or deteriorating. cracked or rusted weldsInspect bracing on decks and balconies for undue structural movementMarch 2017Page 15 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyBearers and joistsBearers and joists are vital to the integrity of a deck or balcony. Bearers support the joists, which in turnsupport the decking. It is important that bearers and joists are in good condition and free from defectssuch as warping and cracking.What to look for: warped, cracked or damaged bearers or joists. decay and looseness at butt joints and termite damageCheck bearers and joists for warping or crackingLedgers or pole platesDecks and balconies are often attached to the main external walls of the house or other structure such asa pool, by supporting joists or bearers off ledgers or pole plates. These members have to have adequatestructural connections to their supporting structure which may mean connecting them through theexternal wall cladding to the structural frame of the house. It is common for brick veneer houses that havea deck added to just use a masonry fastener (expanding anchor) to connect the ledger or pole plate andthis is not usually an acceptable, structurally adequate connection. Ledgers or pole plates connected tobrick veneer should be thoroughly checked for their adequacy.Decking boardsDecking boards are the direct link between inhabitants and the structure. Timber boards should beinspected for decay regularly. Signs of decay include a fungus type growth on the timber, timberbecoming spongy and fibrous and failure of the timber. Using a screwdriver or chisel to poke suspecttimber can assist in identifying decay.Investigation methodWhere warranted, a small diameter (3 to 4mm) drill could be used to detect internal decay in timberwhich may not always be detectable on the outside of the timber. Decayed timber will have lessresistance to the penetration of the drill and would indicate more intrusive investigation is necessary.This procedure should be used carefully as it may compromise the structure. An epoxy repair kit can beused to repair the drill hole.March 2017Page 16 of 21
Deck, balcony and window safety: Guideline – Building Industry and PolicyWhat to look for: warped, cracked or damaged decking boards. signs of decay in timber.Examples of decking board decayBalustradesAnchor points of the balustrade should be inspected regularly to ensure these are free from deterioration.Any weakening of these anchors could cause them to fail if a load was applied to the balustrade, such asa person leaning against the balustrade.What to look for: rust and wear at anchor points (where the balustrade is fixed to the deck or balcony, walls or posts) handrail is securely fastened to the balustrade glass balustrades are free from chips or cracks openings in balustrade must comply with the relevant building standards.Helpful hintIf you can disp
: Guideline –Building Industry and PolicyDeck, balcony and window safety March 2017 Page 4 of 21 Coroner Reports 2010 Coroner’s report into deck collapse In June 2010, the Brisbane Coroner release
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